Re: learning scheme with kawa

[Debabrata Pani <debabrata dot pani at gmail dot com>]

Thank you for the information, Per.
On changing the method name shorter? -> is_shorter? it works fine.

Of course your suggestion to modify the behavior makes sense as well.

Regards,
Debabrata Pani

On Mon, Oct 26, 2015 at 12:06 AM, Per Bothner <per@bothner.com> wrote:
>
>
> On 10/25/2015 10:59 AM, Debabrata Pani wrote:
>>
>> Is this a known discrepancy in the behavior of kawa?
>>
>> Are we violating any RNRS rule when we do this ?
>
>
> It's a Kawa feature that is misbehaving.
>
> As a work-around, try using require instead of load:
>
> (require âreciprocal.ssâ)
>
> This causes the whole file to be processed as a unit,
> so the definition of shorter? is visible when compiling shorter.
>
> The gory details:
>
> The "feature" is that Kawa has special handling when it
> sees TYPE? .  If there is no known definitions of TYPE?,
> but there is a known definition of TYPE then it will
> convert the TYPE? to '(lambda (obj) (instance? obj TYPE))'
>
> In this case, the Kawa compiler sees shorter?, there is (yet) no
> definition of shorter?, but there is one of shorter, so it
> does the above transformation.
>
> I think this is a Kawa bug.  It should only convert TYPE?
> to (lambda (obj) (instance? obj TYPE)) when TYPE is actually
> bound to a class or a type.  I'll have to think about the best
> way to do this.
> --
>         --Per Bothner
> per@bothner.com   http://per.bothner.com/